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David Julian Mcclements - One of the best experts on this subject based on the ideXlab platform.
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influence of anionic dietary fibers xanthan gum and pectin on oxidative stability and lipid digestibility of Wheat Protein stabilized fish oil in water emulsion
Food Research International, 2015Co-Authors: Mouming Zhao, David Julian Mcclements, Eric A DeckerAbstract:Abstract The influence of two anionic dietary fibers (xanthan gum and pectin) on the oxidative stability and lipid digestibility of fish oil emulsions stabilized by Wheat Protein (gliadin) was investigated. Lipid oxidation was determined by measuring lipid hydroperoxides and TBARS of the emulsions during storage, while Protein oxidation was measured using fluorescence spectroscopy. Lipid and Protein oxidation was faster at pH 3.5 than at pH 7, which may have been due to increased iron solubility under acidic conditions. Xanthan gum inhibited lipid and Protein oxidation, which was attributed to its ability to bind iron ions. Conversely, pectin promoted oxidation, which was attributed to the presence of endogenous transition metals in the polysaccharide ingredient. In vitro digestion was carried out to evaluate the digestibility of oil droplets in emulsions with or without polysaccharides. Both xanthan gum and pectin significantly increased the rate of lipid digestion, which was attributed to their ability to inhibit droplet aggregation under gastrointestinal conditions. These results have important implications for designing emulsion-based functional foods with improved oxidative stability and lipid digestibility.
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improving the stability of Wheat Protein stabilized emulsions effect of pectin and xanthan gum addition
Food Hydrocolloids, 2015Co-Authors: Mouming Zhao, David Julian McclementsAbstract:Abstract The potential of two anionic polysaccharides, pectin and xanthan gum, to improve the physical stability of emulsions containing lipid droplets coated by Wheat Protein (deamidated gliadin) was investigated. Polysaccharide type and solution pH had a major impact on biopolymer interactions in solution: Wheat Protein interacted with xanthan gum from pH 3.5 to 7, but with pectin from pH 3.5 to 5, which was attributed to different polysaccharide charge densities. Biopolymer interactions in solutions were related to their adsorption behavior in emulsions. Wheat Protein-stabilized emulsions were highly unstable to aggregation at pH values around their isoelectric point (pI ≈ 5) and at elevated NaCl (≥100 mM, pH 7) or CaCl 2 (≥10 mM, pH 7) levels. Adding xanthan gum improved emulsion stability to high ionic strengths, with no phase separation observed during storage for 4 weeks. Adding pectin improved emulsion stability at acidic pH, but the emulsions were still unstable at elevated ionic strengths. These results are useful for the increased utilization of Wheat Proteins as functional ingredients in the food industry.
Mouming Zhao - One of the best experts on this subject based on the ideXlab platform.
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influence of anionic dietary fibers xanthan gum and pectin on oxidative stability and lipid digestibility of Wheat Protein stabilized fish oil in water emulsion
Food Research International, 2015Co-Authors: Mouming Zhao, David Julian Mcclements, Eric A DeckerAbstract:Abstract The influence of two anionic dietary fibers (xanthan gum and pectin) on the oxidative stability and lipid digestibility of fish oil emulsions stabilized by Wheat Protein (gliadin) was investigated. Lipid oxidation was determined by measuring lipid hydroperoxides and TBARS of the emulsions during storage, while Protein oxidation was measured using fluorescence spectroscopy. Lipid and Protein oxidation was faster at pH 3.5 than at pH 7, which may have been due to increased iron solubility under acidic conditions. Xanthan gum inhibited lipid and Protein oxidation, which was attributed to its ability to bind iron ions. Conversely, pectin promoted oxidation, which was attributed to the presence of endogenous transition metals in the polysaccharide ingredient. In vitro digestion was carried out to evaluate the digestibility of oil droplets in emulsions with or without polysaccharides. Both xanthan gum and pectin significantly increased the rate of lipid digestion, which was attributed to their ability to inhibit droplet aggregation under gastrointestinal conditions. These results have important implications for designing emulsion-based functional foods with improved oxidative stability and lipid digestibility.
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improving the stability of Wheat Protein stabilized emulsions effect of pectin and xanthan gum addition
Food Hydrocolloids, 2015Co-Authors: Mouming Zhao, David Julian McclementsAbstract:Abstract The potential of two anionic polysaccharides, pectin and xanthan gum, to improve the physical stability of emulsions containing lipid droplets coated by Wheat Protein (deamidated gliadin) was investigated. Polysaccharide type and solution pH had a major impact on biopolymer interactions in solution: Wheat Protein interacted with xanthan gum from pH 3.5 to 7, but with pectin from pH 3.5 to 5, which was attributed to different polysaccharide charge densities. Biopolymer interactions in solutions were related to their adsorption behavior in emulsions. Wheat Protein-stabilized emulsions were highly unstable to aggregation at pH values around their isoelectric point (pI ≈ 5) and at elevated NaCl (≥100 mM, pH 7) or CaCl 2 (≥10 mM, pH 7) levels. Adding xanthan gum improved emulsion stability to high ionic strengths, with no phase separation observed during storage for 4 weeks. Adding pectin improved emulsion stability at acidic pH, but the emulsions were still unstable at elevated ionic strengths. These results are useful for the increased utilization of Wheat Proteins as functional ingredients in the food industry.
Benjamin T Wong - One of the best experts on this subject based on the ideXlab platform.
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Deamidated Wheat Protein-carbohydrate Maillard conjugates : effect of size, location and number of carbohydrate conjugated on emulsion steric stabilization at acidic pH and in ionic environment
2017Co-Authors: Benjamin T WongAbstract:This study investigated the effects of conjugation of deamidated Wheat Protein (sIWP – 40,375 Da) with carbohydrate (180 – 41,000 Da) on the Protein’s solution properties (e.g. pI, aggregation behavior at acidic pH, secondary structure, tryptophan local environment), interfacial properties (e.g. interfacial layer thickness) and the ability to stabilize an oil-in-water (O/W) emulsion at acidic pH and in ionic environments. The Protein-carbohydrate conjugates were prepared via the Maillard reaction by dry heating at 60 ºC/75% relative humidity. The carbohydrates used were glucose (180 Da), maltodextrins (900 – 4,300 Da), and dextrans (6,400 – 41,000 Da). Approximately 3 – 4 moles of glucose or low molecular weight (LMW) carbohydrate fraction in the 900 – 4,300 Da maltodextrins (i.e. < 425 Da) were conjugated per mole of sIWP, whereas approximately 1.3 mole or 0.5 mole of dextran (6,400 Da or 41,000 Da) was conjugated per mole of sIWP. The zeta-potential and the circular dichroism spectra of the sIWP/Protein-conjugates indicate that conjugation did not change the Protein’s pI (~pH 4) or the Protein’s secondary structure in solution. sIWP and the Protein-conjugates attached with glucose or LMW carbohydrates in the maltodextrins became aggregated in solution when the pH approached the pI. Conversely, Protein-conjugates attached with dextrans were aggregated to lower extent in solution than sIWP at its pI due to the conjugated dextran acting as a physical barrier. Dynamic light scattering was used to study the interfacial layer thickness of sIWP/Protein-conjugates adsorbed on polystyrene spheres model system. sIWP alone formed a thick Protein steric layer of ~18 nm at the interface. Protein-conjugates attached with glucose or LMW carbohydrates in the maltodextrins showed the same layer thickness as sIWP (i.e. ~18 nm), indicating that the attached carbohydrates did not formed an additional carbohydrate steric layer at the interface due to their small sizes. On the other hand, Protein-conjugates attached with dextrans (6,400 Da and 41,000 Da) were able to form a thicker interfacial layer by ~3.5 nm and ~5.9 nm respectively than sIWP. Dextranase digestion on the interfacial layer indicates that an additional carbohydrate steric layer was formed by the Protein-conjugate attached with 41,000 Da dextran, but was not with 6,400 Da dextran. The observed difference between the attachments of two dextrans with different MW was due to the difference in the sites of conjugation. The smaller 6,400 Da dextran was attached at the C-terminal domain of sIWP, which is the anchoring point to the interface as suggested by the change in the local environment of the tryptophan residues located at the C-terminal domain of sIWP, whereas the larger 41,000 Da dextran was attached at the N-terminal domain of sIWP, as part of the Protein diffuse layer. Emulsion stabilized by Protein-conjugates attached with LMW carbohydrates in the maltodextrin, or the smaller 6,400 Da dextran became flocculated in acidic pH (pH 4) and in CaCl2 environments (0 – 20 mM), similar to the emulsion stabilized by sIWP. However the emulsion stabilized by the Protein-conjugate formed with the larger 41,000 Da dextran was stable in acidic pH (pH 4) and in CaCl2 environments (0 – 20 mM). This is due to the additional carbohydrate steric layer formed by the attached dextran which provided adequate steric stability against emulsion droplets flocculation. This study showed that Maillard conjugation can be used to improve the ability of Protein (e.g. sIWP) in stabilizing emulsions at acidic pH and in ionic environments by forming an additional carbohydrate steric layer at the interface. However the formation of an effective carbohydrate steric layer is dependent on the size of the carbohydrate, the location of conjugation and the number of carbohydrate conjugated. [Appendices not included
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deamidated Wheat Protein dextran maillard conjugates effect of size and location of polysaccharide conjugated on steric stabilization of emulsions at acidic ph
Food Hydrocolloids, 2011Co-Authors: Benjamin T Wong, Li Day, Mary Ann AugustinAbstract:A soluble isolated Wheat Protein fraction (sIWP) prepared from commercially deamidated Wheat Protein (30–35% deamidation) was incubated with dextrans D10 or D65 (MW 6400 Da or 41,000 Da) at 60 °C and 75% relative humidity to form Maillard type complexes. After 72 h reaction, approximately 1–2 smaller dextran D10 molecules were attached to per Protein molecule whereas only about 0.5 mol of the larger dextran D65 was attached to per Protein molecule. Both sIWP–dextran complexes formed a thicker interfacial layer at the surface of the polystyrene particles (23.6 nm and 21.2 nm for the sIWP–D65 and sIWP–D10 respectively) than that adsorbed Protein alone (17.7 nm). Both conjugates provided enhanced steric stabilization of the emulsions at acidic pH (∼pH 4), with the sIWP–D65 conjugate being more effective than the sIWP–D10 conjugate even though there was lower number of dextran D65 molecules conjugated to the Protein. This is because that the conjugation of larger size dextran D65 was preferred at the N-terminal domain and thus provided an additional steric layer of ∼6 nm thickness in addition to the Protein layer at the oil-in-water emulsion interface which is sufficient to provide steric repulsion for the oil droplets even in the absence of electrostatic repulsion. The number of dextrans conjugated to the Protein and the location of conjugation was dependent on the size of the dextran. This, in turn, influenced the ability of conjugates to form effective interfacial steric layer and to maintain emulsion stability at acidic pH (∼pH 4).
Eishin Morita - One of the best experts on this subject based on the ideXlab platform.
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Higher allergenicity of high molecular weight hydrolysed Wheat Protein in cosmetics for percutaneous sensitization.
Contact Dermatitis, 2012Co-Authors: Yuko Chinuki, Hitoshi Takahashi, Itaru Dekio, Sakae Kaneko, Reiko Tokuda, Mizuho Nagao, Takao Fujisawa, Eishin MoritaAbstract:Background Wheat Protein derivatives are used in a variety of products worldwide. Gluten is commercially used ‘as is' or with modifications such as hydrolysis, which is carried out to overcome its insolubility. Several cases of contact urticaria following exposure to hydrolysed Wheat Protein (HWP) in cosmetics or of anaphylaxis caused by deamidated gluten in food or non-food products have been described. Objectives To evaluate the types of HWP that have higher allergenicity for percutaneous sensitization. Methods We enrolled 7 patients with Wheat-dependent exercise-induced anaphylaxis who had been sensitized to HWP primarily through the percutaneous and/or the rhinoconjunctival route by using facial soap containing HWP. Reaction to Wheat Proteins was confirmed by IgE immunoblotting and basophil CD203c expression with six HWP variants. Results The IgE of all the patients reacted to HWPs composed of large polypeptide aggregates. High molecular weight (MW) HWPs were also found to induce significant enhancement of basophil CD203c expression. Conclusions HWPs composed of large polypeptide aggregates possibly induce sensitization to a greater degree than lower-MW HWPs. Basophil surface CD203c expression is useful for evaluating the allergenicity of HWPs.
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Wheat dependent exercise induced anaphylaxis sensitized with hydrolyzed Wheat Protein in soap
Allergology International, 2012Co-Authors: Yuko Chinuki, Eishin MoritaAbstract:Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a specific form of Wheat allergy typically induced by exercise after ingestion of Wheat products. Wheat ω-5 gliadin is a major allergen associated with conventional WDEIA, and detection of serum immunoglobulin E (IgE) specific to recombinant ω-5 gliadin is a reliable method for its diagnosis. Recently, an increased incidence of a new subtype of WDEIA, which is likely to be sensitized via a percutaneous and/or rhinoconjunctival route to hydrolyzed Wheat Protein (HWP), has been observed. All of the patients with this new subtype had used the same brand of soap, which contained HWP. Approximately half of these patients developed contact allergy several months later and subsequently developed WDEIA. In each of these patients, contact allergy with soap exposure preceded food ingestion-induced reactions. Other patients directly developed generalized symptoms upon ingestion of Wheat products. The predominant observed symptom of the new WDEIA subtype was angioedema of the eyelids; a number of patients developed anaphylaxis. This new subtype of WDEIA has little serum ω-5 gliadin-specific serum IgE.
Gerald Reese - One of the best experts on this subject based on the ideXlab platform.
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immunoglobulin e reactivity of Wheat allergic subjects baker s asthma food allergy Wheat dependent exercise induced anaphylaxis to Wheat Protein fractions with different solubility and digestibility
Molecular Nutrition & Food Research, 2004Co-Authors: Diana Mittag, Bodo Niggemann, Ingrid Sander, I Reese, Evamaria Fiedler, Margitta Worm, Stefan Vieths, Gerald ReeseAbstract:Baker's asthma, food allergy to Wheat, and Wheat-dependent, exercise-induced anaphylaxis (WDEIA) are different clinical forms of Wheat allergy. We investigated the correlation of solubility and digestion stability of Wheat allergens with the IgE-reactivity patterns of different patient groups. Three Wheat Protein fractions were extracted according to their solubility: salt-soluble albumins and globulins, ethanol-soluble gliadins, and glutenins soluble only after treatment with detergents and reducing reagents. Sera from subjects with history of each variant of Wheat allergy were characterized by CAP FEIA and immunoblotting. There was a high degree of heterogeneity of recognized allergens between the different subject groups as well as within these groups. However, subjects with WDEIA showed similar immunoglobulin E (IgE)-reactivity patterns to gliadins and especially to a 65 kDa Protein. Subjects with baker's asthma as well as the food-allergic subjects had the most intense IgE-reactivity to the albumin/globulin fraction. The latter group additionally showed IgE-reactivity to the other fractions. Divergent results of immunoblotting and CAP-FEIA demonstrated that the detection of Wheat-specific IgE highly depends on the applied method, thus the diagnostic tool must be carefully chosen. Most Wheat allergens were rapidly digested as analyzed by determination of IgE-reactivity on immunoblots to Wheat extracts after simulation of gastric and duodenal digestion. However, ethanol-soluble gliadins were stable to gastric enzymes and exhibit low solubility in gastric and duodenal fluids. Therefore, they are likely to be important in food allergy to Wheat.
